Study of near-field propagating mode profiles and waveguide structures of optical fibers

A novel method using SNOM and AFM to study both optical fiber structures and near-field optical intensity profiles at fiber endfaces has been successfully developed. We have demonstrated that this novel technique is able to probe both refractive index distribution and near-field propagating intensity profile of fiber structures simultaneously. Correlations between waveguide structures and near-field propagating modes can be acquired directly from the experimental images.